def get_breadcrumb(category):
    """
    获取面包屑导航
    :param category:类别对象：一级 二级  三级
    :return:一级：返回一级  二级：返回一级+二级  三级：一级+二级+三级
    """
    breadcrumb = {
        'cat1': '',
        'cat2': '',
        'cat3': '',
    }
    if category.parent == None:  			# 一级类别
        breadcrumb['cat1'] = category
    elif category.subs.count() == 0:  		# 三级类别
        cat2 = category.parent
        breadcrumb['cat1'] = cat2.parent
        breadcrumb['cat2'] = cat2
        breadcrumb['cat3'] = category
    else:  									# 二级类别
        breadcrumb['cat1'] = category.parent
        breadcrumb['cat2'] = category
    return breadcrumb